[TIPS] fox hole radio - amazing!

I had heard that soldiers in WWII used to make radios out in the field, but I had no idea how. Now, Bre Pettis from Make Magazine shows you how to make one from a toilet paper tube, some wire, a couple safety pins, some thumb tacks, a small stub of a pencil, and a razor blade.

 

This is VERY cool, and full of lesson ideas. Why the lead pencil? Why a razor blade? What do the safety pins have to do with it?

 

Check out his video here: http://www.rocketboom.com/vlog/rb_07_sep_19